varying highp vec2 textureCoordinate;                                              
uniform sampler2D inputTexture;                                                    
uniform lowp float brightness;                                                     
                                                                                   
void main()                                                                        
{                                                                                  
    lowp vec4 textureColor = texture2D(inputTexture, textureCoordinate);           
    gl_FragColor = vec4((textureColor.rgb + vec3(brightness)), textureColor.w);    
}                                                                                  